title: Optimized extraction and characterization of antimicrobial phenolic compounds from mangosteen (Garcinia mangostana L.) cultivation and processing waste.
abstract: BACKGROUND
  Applications for antimicrobials derived from the mangosteen (Garcinia mangostana L.) plant are presently restricted by high production costs. Extraction from cultivation or processing waste streams using a solvent-free approach could lessen to permit commercial applications in food processing and preservation.
  
  
  RESULTS
  Phenolics were extracted from mangosteen bark, leaf and fruit pericarp in methanol and in water using response surface methodology to optimize recovery. Initial examination of antimicrobial effects revealed a lack of antimicrobial activity against fungi and weak activity against the Gram-negative bacteria Escherichia coli and Salmonella typhimurium. In contrast, extracts prepared from bark or fruit pericarp exhibited strong pH-dependent bacteriostatic and bactericidal effects against Listeria monocytogenes and Staphylococcus aureus. Activity was slightly weaker in aqueous extracts due to lower concentrations of tartaric acid esters and flavonols than in methanolic extracts. Measurement of propidium iodide uptake and ATP leakage indicated that the extracts induced damage to the membrane of Gram-positive bacteria.
  
  
  CONCLUSIONS
  Extracts of mangosteen bark and fruit pericarp contain mixtures of phenolic compounds with activity against Gram-positive bacteria, notably Listeria monocytogenes. Extraction of phenolics from mangosteen waste could yield fractions for potential applications in the formulation of low-cost processing aids or sanitizers for the food industry.
authors.affiliation: Department of Food Technology, Faculty of Agro-Industry, Prince of Songkla University, Hat Yai, Songkhla, 90112, Thailand.
authors.forename: Choothaweep
authors.initials: C
authors.lastname: Palakawong
authors.forename: Pairat
authors.initials: P
authors.lastname: Sophanodora
authors.forename: Peter
authors.initials: P
authors.lastname: Toivonen
authors.forename: Pascal
authors.initials: P
authors.lastname: Delaquis
mesh_terms: D000383:Agriculture; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002462:Cell Membrane / Q000187:drug effects; D044948:Flavonols / Q000494:pharmacology; D005511:Food Handling; D005638:Fruit; D029762:Garcinia mangostana / Q000737:chemistry*; D006090:Gram-Negative Bacteria / Q000187:drug effects; D008089:Listeria monocytogenes / Q000187:drug effects*; D008826:Microbial Sensitivity Tests; D010636:Phenols / Q000494:pharmacology*; D024301:Plant Bark; D010936:Plant Extracts / Q000494:pharmacology*; D013211:Staphylococcus aureus / Q000187:drug effects*; D013644:Tartrates / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D044948:Flavonols; D010636:Phenols; D010936:Plant Extracts; D013644:Tartrates; C029768:tartaric acid
keywords: Garcinia mangostana; MBC; MIC; antimicrobials; mangosteen